JP4008694B2 - Sewage treatment plant water quality controller - Google Patents

Description

【００８７】
以上説明したように本実施の形態によれば、
被処理水３の汚濁負荷量が汚濁負荷量の基準値以下の場合、凝集剤注入装置１６は、好気槽１２に凝集剤の注入が行なわず、被処理水３の汚濁負荷量が汚濁負荷量の基準値以上の場合、凝集剤の注入を行なうように制御が行われるため、凝集剤の注入量を最適化できる。また前段水質計５を使用することなく汚濁負荷量を算出できることから、前段水質計５の汚れの付着による前段水質計５の精度の低下および異常信号の問題も解決でき、下水処理場水質制御装置１の信頼性を向上させることができる。さらに、前段水質計５のメンテナンスの手間を省くことができる。
【００８８】
第３の実施の形態
次に図７により本発明の第３の実施の形態について説明する。
【００８９】
図７は、本発明の第３の実施の形態を示している。
【００９０】
図７に示す、第３の実施の形態は、好気槽１２の前段に前段水質計５を設けるとともに、水質予測部１８からの関数に基づいて算出された水質の値と前段水質計５からの水質の値の偏差が予め設定された範囲内にあるか判定を行なう判定部２０とを備えたものである。
【００９１】
図７において、他の構成は図３乃至図６に示す第２の実施の形態と略同一である。図７において、図３乃至図６に示す第２の実施の形態と同一部分には同一の符号を符して詳細な説明は省略する。
【００９２】
図７に示すように、前段水質計５は、信号線５ａ、５ｂを介して判定部２０および水質データベース１７に接続され、判定部２０は、信号線１９ａ、２０ａを介して水質算出部１９および負荷量演算部６に接続されている。
【００９３】
図７に示すように、前段水質計５において計測された計測値は、信号線５ｂを介して水質データベース１７に送信され、水質データベース１７に蓄積される。
【００９４】
また水質予測部１８に現在の外部環境が入力されると、水質予測部１８は、信号線１７ａを介して水質データベース１７に蓄積されたパターンから現在の外部環境に最も近似したパターンを選択し、選択したパターンに基づいて水質と時間の関数を算出する。
【００９５】
水質予測部１８は、算出した水質と時間の関数を信号線１８ａを介して水出算出部１９に送信し、水質算出部１９は、水質予測部１８からの水質と時間の関数に基づいて当該時間に対応する水質の値を算出する。水質算出部１９において算出された当該時間に対応する水質の値は、信号線１９ａを介して判定部２０に送信され、判定部２０は、水質算出部１９から送信された当該時間に対応する水質の値と前段水質計５からの当該時間に対応する水質の値の偏差を算出し、算出された偏差が予め設定された範囲内にあるか判定を行なう。判定部２０は、算出された偏差が予め設定された範囲内であると判断した場合は、前段水質計５は正常であると判断し、前段水質計５からの水質の値を、信号線２０ａを介して負荷量演算部６に送信する。判定部２０は、算出された偏差が予め設定された範囲外であると判断した場合は、前段水質計５は異常（故障、校正による非定常状態）であると判断し、水質算出部１９からの水質の値を、信号線２０ａを介して負荷量演算部６に送信する。ここで、予め設定された範囲は、判定部２０に予め設定されているが、判定部２０において自由に設定変更できるようになっている。
【００９６】
以上説明したように本実施の形態によれば、前段水質計５に異常が発生した場合においても、負荷量演算部６は汚濁負荷量を算出することができる。
【００９７】
第４の実施の形態
次に図８により本発明の第４の実施の形態について説明する。
【００９８】
図８は、本発明の第４の実施の形態を示している。
【００９９】
図８に示す第４の実施の形態は、好気槽１２と最終沈殿池１３の間の配水管ｃに被処理水３中の特定物質の濃度を計測する後段水質計２２を設け、汚濁負荷量と被処理水３の目標水質との間の関数を設定する目標関数設定部２３を設けるとともに、目標関数設定部２３で設定された関数と負荷量演算部６からの汚濁負荷量の値に基づいて制御目標値を算出する制御目標演算部２１とを設けたものである。
【０１００】
図８において、他の構成は図１に示す第１の実施の形態と略同一である。図８において、図１に示す第１の実施の形態と同一部分には同一の符号を符して詳細な説明は省略する。
【０１０１】
図８に示す後段水質計２２としては、アンモニア濃度計が用いられている。
【０１０２】
制御目標演算部２１は、負荷量演算部６と制御部８の間に配置され、制御目標演算部２１には、目標関数設定部２３が接続されている。
【０１０３】
図８に示すように、負荷量演算部６は汚濁負荷量を算出し、算出された汚濁負荷量を制御目標演算部２１に信号線６ａを介して送信する。
【０１０４】
次に目標関数設定部２３は、汚濁負荷量と被処理水３のアンモニア濃度目標値との間の関数（４．１）を設定する（図９）。図９において、縦軸はアンモニア濃度目標値を示し、横軸は汚濁負荷量を示している。
【０１０５】
その後、目標関数設定部２３は、ＩＡＷＱ活性汚泥モデルの理論的モデルを用いたシミュレーションによって、被処理水３の汚濁負荷量と達成可能なアンモニア濃度の関数（ａ）を算出する。ここで目標関数設定部２３は、ＩＡＷＱ活性汚泥モデルの理論的モデルを用いているが、他の理論モデルを用いてもよい。
【０１０６】
次に目標関数設定部２３は、このシュミレーションによって算出した関数（ａ）に基づいて、アンモニア濃度目標値が漸増するような関数（ｂ）を算出し、この関数（ｂ）が目標関数として目標関数設定部２３に設定される（図１０）。図１０において、縦軸は、アンモニア濃度目標値を示し、横軸は汚濁負荷量を示している。
【０１０７】
ＳＶ_ＮＨ４＝Ｈ(Ｐ_{ＮＨ４ｉｎ}) 式（４．１）
なお式（４．１）における各記号を以下のように設定する。
Ｈ（Ｐ_{ＮＨ４ｉｎ}）：汚濁負荷量／目標関数
ＳＶ_ＮＨ４：アンモニア濃度目標値
【０１０８】
目標関数設定部２３において設定された関数（ｂ）は、信号線２３ａを介して制御目標演算部２１に送信される。
【０１０９】
制御目標演算部２１は、目標関数設定部２３で設定された関数（４．１）と負荷量演算部６からの汚濁負荷量の値に基づいてアンモニア濃度目標値（制御目標値）を算出する。制御目標演算部２１において算出されたアンモニア濃度目標値は、信号線２１ａを介して制御部８に送信される。
【０１１０】
制御部８は、制御目標演算部２１で算出されたアンモニア濃度目標値とアンモニア濃度計２２からのアンモニア濃度の値との偏差ｅ_ｔを（４．２）の演算式により算出し、算出された偏差に基づいて、（４．３）の演算式により、曝気装置９の曝気量目標値Ｑａｉｒ_ｔを算出する。
【０１１１】
ｅ_ｔ＝ＰＶ_{ＮＨ４、ｔ}−ＳＶ_{ＮＨ４、ｔ} 式（４．２）
なお式（４．２）における各記号を以下のように設定する。
【０１１２】
ＰＶ_{ＮＨ４、ｔ}：時刻ｔの被処理水３のアンモニア濃度（アンモニア濃度計２２から送信された値）
ＳＶ_{ＮＨ４、ｔ}：時刻ｔの被処理水３のアンモニア濃度目標値（制御目標演算部２１において算出された値）
Ｑａｉｒ_ｔ＝Ｑａｉｒ_ｔ−Δｔ＋Ｋ_ｐｅ_ｔ 式（４．３）
なお式（４．３）における各記号を以下のように設定する。
Ｑａｉｒ_ｔ：時刻ｔにおける曝気量目標値
Ｑａｉｒ_ｔ−Δｔ：時刻ｔ−Δｔにおける曝気量
Ｋ_ｐ：比例定数
Δｔ：時間遅れ
【０１１３】
比例定数Ｋ_ｐおよび時間遅れΔｔは、予め制御部８に設定されているが、制御部８において自由に設定変更できるようになっている。
【０１１４】
制御部８において算出された曝気量目標値は、信号線８ａを介して曝気装置９に送信され、曝気装置９は、曝気量目標値で好気槽１２内を曝気する。
【０１１５】
以上説明したように本実施の形態によれば、
目標関数設定部２３において、ＩＡＷＱ活性汚泥モデルの理論的モデルを用いたシミュレーションによって、被処理水３の汚濁負荷量と達成可能なアンモニア濃度の関数（図９（ａ））を算出し、算出された関数（図９（ａ））に基づいて、アンモニア濃度目標値が漸増するような関数（図９（ｂ））を算出し、この関数（図９（ｂ））を用いることにより、被処理水３の汚濁負荷量が大きくなった場合に、被処理水３に対する曝気量目標値がゆるやかに変化することから、必要以上の曝気を抑制でき、コストの低減を図ることができる。
【０１１６】
次に本発明の変形例について説明する。
【０１１７】
制御目標演算部２１は、目標関数設定部２３で設定された関数（４．１）と負荷量演算部６からの汚濁負荷量の値に基づいてアンモニア濃度目標値（制御目標値）を算出しているが、被処理水３の汚濁負荷量が演算される時点と被処理水３が好気槽１２に流入するまでの時間遅れΔｔを考慮した下記の（４．４）の演算式により、アンモニア濃度目標値（制御目標値）ＳＶ_ｔを算出してもよい。
【０１１８】
ＳＶ_ｔ＝Ｈ（Ｐ_ｔ−Δｔ） 式（４．４）
なお式（４．４）における各記号を以下のように設定する。
ＳＶ_ｔ：アンモニア濃度目標値
Ｐ_ｔ−Δｔ：時間（ｔ一Δｔ）における汚濁負荷量
Δｔ：時間遅れ
【０１１９】
【発明の効果】
本発明によれば、曝気装置による曝気量を常に最適な量に調整し、また凝集剤の注入量を最適な量に調整することができる。さらに汚濁負荷量が大きく変動した場合に、必要以上の曝気をすることなく曝気装置を制御できることから、コストの低減を図ることができる。また、水質計を使用することなく、制御部は、凝集剤注入装置の制御を行なうことから、水質計の付着物の問題を解消でき、下水処理場水質制御装置の信頼性を向上させることができる。
【図面の簡単な説明】
【図１】本発明による下水処理場水質制御装置の第１の実施の形態を示す全体構成図
【図２】ＵＶ値と被処理水のリン濃度との関係を示す図
【図３】本発明による下水処理場水質制御装置の第２の実施の形態を示す全体構成図
【図４】水質データベースを示す図
【図５】水質と時間との関係を示す図
【図６】汚濁負荷量の閾値と汚濁負荷量との関係を示す図
【図７】本発明による下水処理場水質制御装置の第３の実施の形態を示す全体構成図
【図８】本発明による下水処理場水質制御装置の第４の実施の形態を示す全体構成図
【図９】被処理水の汚濁負荷量と達成可能なアンモニア濃度の関数を示す図
【図１０】目標関数設定部に設定される目標関数を示す図
【図１１】従来の高度処理プロセスを示す図
【図１２】従来の下水処理場水質制御装置を示す図
【符号の説明】
１ 下水処理場水質制御装置
４ 流量計
５ 前段水質計
６ 負荷量演算部
７ 基準設定部
８ 制御部
９ 曝気装置
１２ 好気槽
１６ 凝集剤注入装置
１７ 水質データベース
１８ 水質予測部
１９ 水質算出部
２０ 判定部
２１ 制御目標演算部
２２ 後段水質計
２３ 目標関数設定部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sewage treatment plant water quality control apparatus using biological nitrification denitrification reaction, biological dephosphorization reaction and dephosphorization reaction by adding a flocculant, and in particular, efficiently removes nitrogen or phosphorus components. The present invention relates to a sewage treatment plant water quality control device.
[0002]
[Prior art]
In recent years, eutrophication has progressed in lakes, bays, etc., and there is a need to suppress nitrogen and phosphorus, which are the causative substances of eutrophication. Organic substances are removed by a process called activated sludge process at conventional sewage treatment plants, but the demand for advanced treatment that removes nitrogen and phosphorus from the progress of eutrophication in lakes and marshes is increasing. .
[0003]
FIG. 11 shows a conventional advanced process with nitrogen and phosphorus removal.
[0004]
In FIG. 11, the conventional advanced treatment process includes an initial sedimentation tank 2 into which treated water 3 flows from a distribution pipe a, an anaerobic tank 10 connected to the first sedimentation tank 2 through a distribution pipe b, and an anaerobic tank 10. And an oxygen-free tank 11 connected to the. An aerobic tank 12 is connected to the anaerobic tank 11, and a final sedimentation tank 13 is connected to the aerobic tank 12 through a water distribution pipe c. A distribution pipe f through which treated water flows out is connected to the final sedimentation basin 13, and a circulation pump 14 is connected between the aerobic tank 12 and the anoxic tank 11 through a distribution pipe d. A return pump 15 is connected between the aerobic tank 12 and the anaerobic tank 10 via a water distribution pipe e. The aerobic tank 12 is provided with an aeration device 9 and further connected to a flocculant injection pump 16 via a pipe g.
[0005]
Such a conventional advanced processing process includes a coagulant injection anaerobic-anoxic-aerobic method (coagulant injection A).₂A process called “O method” is used.
[0006]
First, a method for removing phosphorus in a conventional advanced processing process will be described.
[0007]
Flocculant injection A₂In the O method, phosphorus removal is performed by the following process.
[0008]
In the anaerobic tank 10 arranged in the front stage of the aeration tank 12, phosphorus accumulating bacteria in the activated sludge are phosphoric acid (PO_Four). In the aerobic tank 12 disposed in the rear stage of the anaerobic tank 10, the excessively released phosphorous-type phosphorus is used by utilizing the phosphorus excessive intake action of the phosphorus accumulating bacteria. Phosphorus removal is performed by absorbing activated phosphorus in activated sludge.
[0009]
In addition to such biological phosphorus removal, phosphorus is removed by injecting an aggregating agent such as polyaluminum chloride, aluminum sulfate and iron sulfate to precipitate the phosphorus component in the form of aluminum phosphate or iron phosphate.
[0010]
Next, a method for removing nitrogen in a conventional advanced processing process will be described.
[0011]
In the aerobic tank 12, ammoniacal nitrogen (NH₄-N) is nitrite nitrogen (NO) by the action of nitrifying bacteria₂-N) and nitrate nitrogen (NO)₃Oxidized to -N). Next, nitrite nitrogen (NO) fed into the anoxic tank 11 by the circulation pump 14₂-N) and nitrate nitrogen (NO)₃-N) is nitrogen gas (N) due to nitrate respiration or nitrite respiration by denitrifying bacteria under anoxic conditions.₂) To be removed from the system.
[0012]
Next, a conventional sewage treatment plant water quality control device will be described.
[0013]
FIG. 12 shows a conventional sewage treatment plant water quality control device.
[0014]
As shown in FIG. 12, the conventional sewage treatment plant water quality control device 1 includes an aeration tank 100 into which the water to be treated 3 flows through the distribution pipe a, and an aeration apparatus 103 that adjusts the amount of aeration in the aeration tank 100. And a final sedimentation basin 101 through which treated water flows out through the water distribution pipe c. A return pump 104 is disposed between the aeration tank 100 and the final sedimentation tank 101, and an ammonia nitrogen concentration meter 105 is attached to the aeration tank 100.
[0015]
A control device 102 that controls the aeration device 103 is connected to the aeration device 103 via a signal line 102a. A control target value setting unit 106 that sets a control target value to the control device 102 via a signal line 106a. Is connected. A controller 102 is connected to the ammonia nitrogen concentration meter 105 via a signal line 105a.
[0016]
In FIG. 12, the control device 102 determines the ammonia nitrogen concentration in the aeration tank 100 based on the deviation between the ammonia nitrogen concentration value from the ammonia nitrogen concentration meter 105 and the control target value from the control target value setter 106. The aeration apparatus 103 is controlled so as to keep it constant.
[0017]
[Problems to be solved by the invention]
In the conventional sewage treatment plant water quality control apparatus 1 shown in FIG. 12, the control apparatus 102 controls the aeration apparatus 103 based on the ammonia nitrogen concentration of the water 3 to be treated after nitrification, and the aeration apparatus 103 is the aeration tank 100. The amount of aeration is adjusted. However, while the amount of treated water 3 flowing into the sewage treatment plant water quality control device 1 varies greatly, the nitrification rate by nitrifying bacteria in the aeration tank 100 is relatively slow. For this reason, the control apparatus 102 controls the aeration apparatus 103 using only the value of the ammonia nitrogen concentration meter 105 after the nitrification treatment, and the aeration apparatus 103 adjusts the aeration amount of the aeration tank 100. When the amount of treated water 3 flowing into the treatment plant water quality control device 1 is large, the amount of aeration in the aeration tank 100 is insufficient, and when the amount of treated water 3 is small, the amount of aeration in the aeration tank 100 is small. It becomes excessive.
[0018]
Further, when the amount of treated water 3 flowing into the sewage treatment plant water quality control device 1 is large, the treated water 3 in the aeration tank 100 undergoes a nitrification reaction until the ammonia concentration target value set in the control target setting device 106 is reached. May not wake up. Therefore, although the aeration amount of the aeration apparatus 103 reaches the maximum value, the state where the ammonia concentration target value is not reached continues and excessive aeration is performed by the aeration apparatus 103, resulting in useless cost. Furthermore, due to excessive aeration by the aeration apparatus 103, the sludge floc is crushed, and the sludge floats up in the final sedimentation basin 101, and this sludge flows out.
[0019]
Ammonia nitrogen concentration meter, nitrate nitrogen concentration meter, total nitrogen concentration meter and other nitrogen component concentration meters installed in sewage treatment plants, and phosphorus component concentration meters such as phosphorus concentration meter and total phosphorus concentration meter, 3 is liable to adhere to dirt due to the floating components in FIG. 3 and often shows an abnormal value. Therefore, it is unstable and difficult to use as a sensor for control. Furthermore, the sampled water 3 is sampled by a sampling pipe, and then the sampled treated water 3 is filtered. Even when the filtered treated water 3 is measured with the above-described concentration meter, the sampling pipe is clogged. The problem is occurring.
[0020]
In the aeration tank 100, it is difficult to remove phosphorus without injecting a flocculant such as polyaluminum chloride. However, there is a problem of high cost due to overinjection of the flocculant and outflow of polyaluminum chloride into the treated water. It has become.
[0021]
The present invention has been made in consideration of such points, and provides a water quality control device for a sewage treatment plant that can always adjust the amount of aeration by the aeration device to an optimum amount and reduce the cost. With the goal.
[0022]
[Means for Solving the Problems]
The present invention is a sewage treatment plant water quality control device installed in a sewage treatment plant that treats incoming polluted water, an aerobic tank, a flow meter that is provided in the front stage of the aerobic tank, and measures the flow rate of the polluted water, A pre-stage water quality meter that measures water quality in polluted water, a load amount calculation unit that calculates a pollutant load amount based on information from the flow meter and the pre-stage water quality meter, and a pollutant load amount. A reference setting unit for setting a reference value, an aeration device for aeration in the aerobic tank,
A sewage treatment plant water quality comprising: a control unit that controls the aeration apparatus based on a deviation between the value of the pollution load from the load calculation unit and the reference value of the pollution load from the reference setting unit It is a control device.
[0023]
According to the present invention, it is possible to always adjust the amount of aeration by the aeration apparatus to an optimal amount, thereby reducing the cost.
[0024]
The present invention is a sewage treatment plant water quality control device installed in a sewage treatment plant that treats incoming treated water, an aerobic tank, and a flow rate that measures the flow rate of the treated water, provided in the front stage of the aerobic tank. The pattern of the relationship between water quality and time determined by the change in the external environment with respect to the water to be treated and the water to be treated is set in advance, and the pattern closest to the current external environment is selected from the set pattern, and based on the selected pattern A water quality prediction unit that calculates a function of water quality and time, a water quality calculation unit that calculates water quality corresponding to the time determined based on the function from the water quality prediction unit, and a function determined from the function of the water quality Based on the water quality value corresponding to the time and the flow rate value from the flow meter, a load amount calculation unit that calculates the pollution load, a reference setting unit that sets a reference value for the pollution load, and an aerobic tank Inject flocculant into And a control unit for controlling the flocculant injection device based on a deviation between the value of the pollution load from the load amount calculation unit and the reference value of the pollution load from the reference setting unit. Is a water quality control device for a sewage treatment plant.
[0025]
According to the present invention, the injection amount of the flocculant can be adjusted to an optimal amount, and the cost can be reduced. In addition, since the control unit controls the flocculant injection device without using a water quality meter, it can solve the problem of deposits on the water quality meter and improve the reliability of the water quality control device for the sewage treatment plant. it can.
[0026]
The present invention is a sewage treatment plant water quality control device installed in a sewage treatment plant that treats incoming treated water, an aerobic tank, and a flow rate that measures the flow rate of the treated water, provided in the front stage of the aerobic tank. A pre-stage water quality meter that is provided at the front of the aerobic tank and measures the concentration of the specific substance in the treated water, and a post-stage water quality that is provided at the rear of the aerobic tank and measures the concentration of the specific substance in the treated water A load amount calculation unit that calculates a pollutant load based on information from the meter, a flow meter and a pre-stage water quality meter, a reference setting unit that sets a reference value for the pollutant load, A target function setting unit that sets a function between the target water quality and a control target calculation unit that calculates a control target value based on the function set in the target function setting unit and the value of the pollution load from the load amount calculation unit The aeration device for aeration in the aerobic tank and the control calculated by the control target calculation unit A sewage treatment plant water quality control apparatus characterized by comprising: a control unit for controlling the aeration device based on a deviation between the value of water quality from target values and subsequent water meter, the.
[0027]
According to the present invention, when the pollution load greatly fluctuates, it is possible to control the aeration apparatus without performing aeration more than necessary, so that the cost can be reduced.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
First embodiment
A first embodiment of a sewage treatment plant water quality control apparatus according to the present invention will be described below with reference to FIGS. 1 and 2.
[0029]
FIG. 1 is a diagram showing a first embodiment of a sewage treatment plant water quality control apparatus according to the present invention.
[0030]
As shown in FIG. 1, a sewage treatment plant water quality control device 1 according to the present invention is connected to a first sedimentation basin 2 into which treated water 3 flows through a distribution pipe a, and to the first sedimentation basin 2 via a distribution pipe b. The anaerobic tank 10, the anaerobic tank 11 connected to the anaerobic tank 10, the aerobic tank 12 connected to the anaerobic tank 11, and the final precipitation connected to the aerobic tank 12 through the water pipe c And a pond 13. Among these, in the water distribution pipe b provided between the first sedimentation basin 2 and the anaerobic tank 10, a flow meter 4 for measuring the flow rate of the water to be treated 3 and a pre-stage for measuring the concentration of the specific substance in the water to be treated 3. A water quality meter 5 is attached. As the pre-stage water quality meter 5, an ammonia concentration meter is used, but a nitrogen component concentration meter or a phosphorus component concentration meter may be used.
[0031]
As the nitrogen concentration meter, either an ammonia nitrogen concentration meter or a total nitrogen concentration meter may be used.
[0032]
Further, the aerobic tank 12 is provided with an aeration apparatus 9 for aerating the inside of the aerobic tank 12.
[0033]
The aerobic tank 12 and the anoxic tank 11 are connected by a water pipe d to which a circulation pump is attached. The final sedimentation basin 13 and the anaerobic tank 10 are connected by a water pipe e to which a return pump 15 is attached. Further, a flocculant injection device 16 is connected to the aerobic tank 12 through a pipe g.
[0034]
A load amount calculation unit 6 that calculates a pollutant load amount based on information from the flow meter 4 and the previous-stage water quality meter 5 is connected to the flow meter 4 and the previous-stage water quality meter 5 via signal lines 4a and 5a.
[0035]
In addition, a control unit 8 that controls the aeration device 9 is connected to the load amount calculation unit 6 via the signal line 6a, and a reference for setting a reference value of the pollutant load amount to the control unit 8 via the signal line 7a. A setting unit 7 is connected. The control unit 8 is connected to the aeration device 9 via the signal line 8a, and the control unit 8 controls the aeration amount of the aeration device 9. Connected to the control unit 8 are a carbon source input device 31 that inputs a carbon source into the aerobic tank 12 and an excess sludge extraction device 30 that extracts excess sludge from the aerobic tank 12.
[0036]
Further, the circulation pump 14, the return pump 15, the flocculant injecting device 16, the surplus sludge extraction device 30, and the carbon source charging device 31 are connected to the control unit 8 through a signal line 8a.
[0037]
Next, the operation of the embodiment having such a configuration will be described.
[0038]
As shown in FIG. 1, the water to be treated 3 flows into the first sedimentation basin 2 through the distribution pipe a, and then flows out from the first sedimentation basin 2 into the anaerobic tank 10 through the distribution pipe b. The treated water 3 treated in the anaerobic tank 10 flows out to the anaerobic tank 11, is oxygen-free in the anoxic tank 11, and then flows out to the aerobic tank 12.
[0039]
In addition, aeration from the aeration device 9 is performed on the water to be treated 3 in the aerobic tank 12 so that the water to be treated 3 is aerobically treated. The treated water 3 in the aerobic tank 12 then flows into the final sedimentation basin 13 where the sedimentation process is performed. The treated water 3 in the final sedimentation basin 13 becomes treated water and is discharged to the outside through the water distribution pipe f. Further, the sludge in the aerobic tank 12 is returned to the anoxic tank 11 by the circulation device 14. The sludge in the final sedimentation tank 13 is returned to the anaerobic tank 10 by the return device 15.
[0040]
During this time, the flow meter 4 provided in the water distribution pipe b measures the flow rate of the treated water 3 flowing in the water distribution pipe b, and transmits the measurement signal to the load amount calculation unit 6 through the signal line 4a. Further, the ammonia concentration meter 5 provided in the distribution pipe b measures the ammonia concentration in the treated water 3 flowing in the distribution pipe b, and transmits the measurement signal to the load amount calculation unit 6 through the signal line 5a. To do.
[0041]
Based on the measurement signal from the flow meter 4 and the measurement signal from the ammonia concentration meter 5, the load amount calculation unit 6 performs the following calculation (1.1) to calculate the pollution load amount. The load amount calculation unit 6 transmits the calculated pollution load amount to the control unit 8 through the signal line 6a.
[0042]
P_NH4in= Qin ・ C_NH4in        Formula (1.1)
Each symbol in formula (1.1) is set as follows.
P_NH4in: Pollution load
Qin: Flow rate of the water to be treated 3 from the flow meter 4
C_NH4in: Ammonia concentration of treated water 3 from ammonia concentration meter 5
[0043]
The reference setting unit 7 receives the average concentration of ammonia and the average flow rate of the water to be treated. The reference setting unit 7 performs the following (1) based on the input average concentration of ammonia and the average flow rate of the water to be treated. Perform the calculation of .2) to calculate the reference value of the pollution load. The reference setting unit 7 transmits the calculated reference value of the pollution load amount to the control unit 8 via the signal line 7a.
[0044]
P _NH4in= Qave_in・ Cave_NH4in        Formula (1.2)
Each symbol in equation (1.2) is set as follows.
P _NH4in: Standard value of pollution load
Qave_in: Average flow rate of treated water 3
Cave_NH4in: Average concentration of ammonia in treated water 3
[0045]
The control unit 8 performs the following calculation (1.3) based on the deviation between the pollutant load amount from the load amount calculating unit 6 and the reference value of the pollutant load amount from the reference setting unit 7. An aeration amount target value is calculated. The control unit 8 transmits the calculated aeration amount target value to the aeration device 9 via the signal line 8a, and the aeration device 9 aerates the inside of the aerobic tank 12 with the aeration amount target value.
[0046]
Qair = Q₀+ Kp (P_NH4in−P _NH4in) Formula (1.3)
Each symbol in equation (1.3) is set as follows.
Kp: proportional constant
Q₀: Constant (Aeration amount required during average pollution load)
[0047]
Constant Q₀As described above, the value of the aeration amount required at the time of the average pollution load is set in the control unit 8 in advance, but a calculated value by the constant air magnification control or the constant DO control may be set. The proportional constant Kp is set in the control unit 8 in advance, but the control unit 8 can freely change the setting.
[0048]
As described above, according to the present embodiment, by attaching the flow meter 4 and the pre-stage water quality meter 5 to the water distribution pipe b, it is possible to improve the accuracy of calculation of the pollution load. In addition, since the average pollution load, which is the value obtained by multiplying the average concentration of a specific substance in the water to be treated 3 by the average flow rate of the water to be treated 3, is used as the reference value of the pollution load, A necessary amount of aeration can be sent to the aerobic tank 12. Furthermore, Kp and Q as setting constants₀Since only these two parameters are used, the adjustment of the parameters is easy.
[0049]
Next, a modified example of the present invention will be described.
[0050]
(1) The load amount calculation unit 6 calculates the pollutant load amount based on the flow rate of the treated water 3 from the flow meter 4, but based on the water level value from the water level meter of the circulation device 14 or the return device 15. Thus, the QH curve may be calculated, and the flow rate of the water to be treated 3 may be calculated from the QH curve.
[0051]
(2) The control unit 8 controls the aeration device 9 based on the deviation between the value of the pollutant load from the load calculating unit 6 and the reference value of the pollutant load from the reference setting unit 7. 15, at least one of the excess sludge extraction device 30, the circulation device 14, the flocculant injection device 16, and the carbon source charging device 31, and the pollution load value from the load amount calculation unit 6 and the pollution from the reference setting unit 7. You may control based on the deviation with the reference value of load amount.
[0052]
(3) The control unit 8 performs the above calculation (1.3) based on the deviation between the pollutant load amount from the load amount calculating unit 6 and the reference value of the pollutant load amount from the reference setting unit 7, and aeration Although the aeration amount target value of the apparatus 9 is calculated, the following point is considered in consideration of the time delay Δt until the pollutant load amount of the water to be treated 3 is calculated and the water 3 to be treated flows into the aerobic tank 12. The aeration amount target value of the aeration apparatus 9 may be calculated by performing the calculation of (1.4).
[0053]
Qair, t = Q_{0 , t}+ Kp (P_{NH4in . t - △ t}-P _NH4in) Formula (1.4)
In addition, each symbol in Formula (1.4) is set as follows.
Qair, t: Aeration amount target value at time t
P_{NH4in . t - △ t}: Pollution load in time (t-Δt)
Δt: time delay
[0054]
The time delay Δt is set in the control unit 8 in advance, but the setting can be freely changed in the control unit 8.
[0055]
(4) The load amount calculation unit 6 calculates the pollution load amount using the measured value from the ammonia concentration meter 5 for the ammonia concentration of the water to be treated 3, but the UV meter, turbidity meter, COD meter The ammonia concentration of the water to be treated 3 is calculated from the correlation between the values measured by the BOD meter and the flow meter 4 and the ammonia concentration set in the load amount calculation unit 6 in advance, and the calculated ammonia concentration is used for contamination. The load amount may be calculated.
[0056]
A phosphorus concentration meter is used as the pre-stage water quality meter 5. Instead of measuring the phosphorus concentration of the water to be treated by the phosphorus concentration meter, the load amount calculation unit 6 is obtained by the correlation between the UV value from the UV meter and the phosphorus concentration. The method for calculating the phosphorus concentration will be described with reference to FIG.
[0057]
FIG. 2 is a diagram showing the relationship between the UV value and the phosphorus concentration of the water to be treated.
[0058]
In FIG. 2, each plot is obtained by sampling the treated water 3 in advance, measuring each sampling, and plotting it on a graph. Furthermore, the correlation equation (y = 0.169x-3.61, R²= 0.7554) is a correlation equation calculated based on each plot in FIG.
[0059]
The UV value increases or decreases depending on the number of C = C (carbon) double bond moieties, and the ratio of the double bond moieties to the phosphorus concentration is approximately constant. The value shows a high correlation.
[0060]
The correlation equation calculated in this way is set in advance in the load amount calculation unit 6, and the load amount calculation unit 6 uses the UV meter based on the set correlation equation instead of the measurement value from the phosphorus concentration meter. Using the UV value, the phosphorus concentration is calculated.
[0061]
Furthermore, the above calculation method uses a single-phase relationship between the UV value and the phosphorus concentration, but the nitrogen component or phosphorus component concentration data of the sewage treatment plant and the values from two or more other water quality meters or flow meters From the multiple phase relationship, the nitrogen component or phosphorus component concentration of the water to be treated 3 may be obtained by the following equation (1.5).
[0062]
C_NorPin= A₁C₁+ A₂C₂+... + B Formula (1.5)
In addition, each symbol in Formula (1.5) is set as follows.
C_NorPin: Nitrogen component concentration or phosphorus component concentration of treated water 3
a₁, A₂···:constant
b: Constant
C₁, C₂...: Values from water quality meters other than nitrogen or phosphorus concentration meters
[0063]
As described above, in sewage treatment plants where phosphorus component concentration and nitrogen component concentration meters are not installed, or in sewage treatment plants where phosphorus component concentration and nitrogen component concentration meters are installed but often show abnormal values, etc. If the online sensor is attached, the load amount calculation unit 6 calculates the phosphorus concentration and the nitrogen component concentration by using the measured values of the other online sensors instead of the phosphorus component concentration and nitrogen component concentration meter. be able to.
[0064]
(5) The target process may be used for any of the processes described below. Various processes such as carrier loading, coagulant combined process, AOAO method, etc.₂You may use for any modification of O method.
[0065]
1) Standard activated sludge method
2) A₂O method (anaerobic-anoxic-aerobic method)
3) AO method (anaerobic-aerobic method)
4) Nitrification endogenous denitrification method
5) Circulating nitrification denitrification method
6) OD method
7) Step injection method
8) Batch activated sludge method
9) Intermittent aeration
10) Activated sludge method with carrier
11) Carrier input A₂O method
12) AO method with carrier
13) Nitrogen endogenous denitrification method with carrier
14) Circulating nitrification denitrification method with carrier
15) Carrier loading OD method
16) Carrier injection step injection method
17) Batch input activated sludge method
18) Intermittent aeration with carrier
19) Coagulant injection type activated sludge method
20) Flocculant injection A₂O method
21) Coagulant injection AO method
22) Coagulant injection nitrification endogenous denitrification method
23) Coagulant injection circulation nitrification denitrification method
24) Coagulant injection OD method
25) Flocculant injection step injection method
26) Coagulant injection batch activated sludge method
27) Flocculant injection intermittent aeration method
28) Membrane separation activated sludge method
29) Membrane separation type A₂O method
30) Membrane separation AO method
31) Membrane separation nitrification endogenous denitrification method
32) Membrane separation type circulation nitrification denitrification method
33) Membrane separation OD method
34) Membrane separation type step injection method
35) Membrane separation type batch activated sludge method
36) Membrane separation type intermittent aeration method
Second embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS.
[0066]
FIG. 3 shows a second embodiment of the present invention.
[0067]
In the second embodiment shown in FIG. 3, the water quality database 17 in which the pattern of the relationship between the water quality and time determined by the change in the external environment with respect to the water to be treated 3 is stored, is deleted, Water quality that is connected to the water quality database 17 via the signal line 17a, selects a pattern that most closely approximates the current external environment from the patterns set in the water quality database 17, and calculates a function of water quality and time based on the selected pattern A prediction unit 18 and a water quality calculation unit 19 connected to the water quality prediction unit 18 through a signal line 18a and calculating a water quality corresponding to the time based on a function of the water quality and the time from the water quality prediction unit 18 are provided. Is.
[0068]
In FIG. 3, the other configurations are substantially the same as those of the first embodiment shown in FIG. In FIG. 3, the same parts as those in the first embodiment shown in FIG.
[0069]
As shown in FIG. 4, the water quality database 17 includes an external environment (date, day of the week, weather, season, rainfall start time, etc.) obtained from a daily water quality test of the treated water 3 flowing into the target sewage treatment plant. The relationship pattern (FIG. 4 (B)) between the water quality and time determined by (rainfall, etc.) (FIG. 4 (A)) is stored.
[0070]
Here, the vertical axis in FIGS. 4A and 4B represents phosphorus concentration (mg / L), and the horizontal axis represents time.
[0071]
Further, a flocculant injection device 16 for injecting the flocculant into the aerobic tank 12 is connected to the control unit 8 through the pipe g.
[0072]
When the current external environment is input to the water quality predicting unit 18, the water quality predicting unit 18 selects a pattern most similar to the current external environment from the patterns set in the water quality database 17 via the signal line 17a.
[0073]
The water quality predicting unit 18 interpolates (FIG. 5) the missing values in the selected relationship pattern between the water quality and time (FIG. 4B) by a straight line and a curve (FIG. 5), so that the water quality and time function (2.1) Is calculated. Here, the vertical axis in FIG. 5 indicates phosphorus concentration (mg / L), and the horizontal axis indicates time. Further, as described above, the water quality and time function (2.1) is calculated by the water quality prediction unit 18, but the water quality and time function (2.1) is freely set in the water quality prediction unit 18. It can be changed.
[0074]
C_TP= G (t) Formula (2.1)
Each symbol in equation (2.1) is set as follows.
C_TP: Phosphorus concentration
t: time
G (t): Function of water quality and time
[0075]
The water quality and time function (2.1) calculated in the water quality prediction unit 18 is sent to the water quality calculation unit 19 via the signal line 18a, and the water quality calculation unit 19 receives the water quality and time function from the water quality prediction unit 18. The phosphorus concentration corresponding to the time t is calculated based on (2.1), and the calculated phosphorus concentration is transmitted to the load amount calculation unit 6 through the signal line 19a.
[0076]
Based on the calculated phosphorus concentration and the value of the flow rate from the flow meter 4, the load amount calculation unit 6 calculates the pollutant load amount by the following equation (2.2).
[0077]
P_T-Pin= Qin ・ C '_T-Pin        Formula (2.2)
Each symbol in equation (2.2) is set as follows.
P_T-Pin: Pollution load
Qin: Flow rate from the flow meter
C '_T-Pin: Phosphorus concentration corresponding to time t
[0078]
The pollutant load amount calculated by the load amount calculation unit 6 is transmitted to the control unit 8 via the signal line 6a.
[0079]
In the reference setting unit 7, a reference value of the pollution load is set in advance. Further, as a reference value of the pollutant load amount, the threshold value of the pollutant load amount that can achieve the target value of the predetermined phosphorus concentration without injecting the flocculant into the aerobic tank 12 is an arithmetic expression of (2.3) below It is set by.
[0080]
P _T-Pin= P_P04th        Formula (2.3)
Each symbol in equation (2.3) is set as follows.
P _T-Pin: Standard value of pollution load
P_P04th: Threshold of pollutant load
[0081]
The reference setting unit 7 calculates the relationship between the pollution load amount and the threshold value of the pollution load amount by simulation using the theoretical model of the IAWQ activated sludge model (FIG. 6). You may calculate the threshold value of pollution load.
[0082]
In FIG. 6, the vertical axis indicates the threshold value of the pollutant load, and the horizontal axis indicates the pollutant load.
[0083]
The reference setting unit 7 transmits the set reference value of the pollutant load amount to the control unit 8 through the signal line 7a.
[0084]
Based on the reference value of the pollutant load amount from the reference setting unit 7 and the pollutant load amount calculated from the load amount calculating unit 6, the control unit 8 calculates the flocculant from the calculation formula (2.4) below. Calculate the injection volume. In the calculation formula (2.4) below, the control unit 8 performs the calculation (A) when the calculated pollution load is larger than the reference value of the pollution load, and the calculated pollution load is When it is below the reference value of the pollutant load, the calculation of (B) is performed.
[0085]
Next, the control unit 8 controls the coagulant injection device 16 so as to inject the coagulant into the aerobic tank 12 with the calculated injection amount of the coagulant via the signal line 8a.
[0086]
[Expression 1]

[0087]
As described above, according to the present embodiment,
When the pollutant load amount of the water to be treated 3 is equal to or less than the reference value of the pollutant load amount, the flocculant injecting device 16 does not inject the flocculant into the aerobic tank 12, and the pollutant load amount of the untreated water 3 is the pollutant load. When the amount is equal to or larger than the reference value, control is performed so as to inject the flocculant, so that the amount of flocculant injected can be optimized. In addition, since the pollution load can be calculated without using the pre-stage water quality meter 5, it is possible to solve the problem of deterioration in accuracy and abnormal signals of the pre-stage water quality meter 5 due to the adhesion of dirt on the pre-stage water quality meter 5. 1 reliability can be improved. Furthermore, the maintenance work of the pre-stage water quality meter 5 can be saved.
[0088]
Third embodiment
Next, a third embodiment of the present invention will be described with reference to FIG.
[0089]
FIG. 7 shows a third embodiment of the present invention.
[0090]
In the third embodiment shown in FIG. 7, the pre-stage water quality meter 5 is provided in the front stage of the aerobic tank 12, and the water quality value calculated based on the function from the water quality prediction unit 18 and the pre-stage water quality meter 5 And a determination unit 20 for determining whether the deviation of the water quality value is within a preset range.
[0091]
In FIG. 7, other configurations are substantially the same as those of the second embodiment shown in FIGS. In FIG. 7, the same parts as those of the second embodiment shown in FIGS. 3 to 6 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0092]
As shown in FIG. 7, the pre-stage water quality meter 5 is connected to the determination unit 20 and the water quality database 17 via signal lines 5a and 5b, and the determination unit 20 is connected to the water quality calculation unit 19 and the signal lines 19a and 20a. The load amount calculation unit 6 is connected.
[0093]
As shown in FIG. 7, the measurement value measured by the pre-stage water quality meter 5 is transmitted to the water quality database 17 via the signal line 5 b and accumulated in the water quality database 17.
[0094]
When the current external environment is input to the water quality prediction unit 18, the water quality prediction unit 18 selects a pattern that most closely approximates the current external environment from the patterns accumulated in the water quality database 17 via the signal line 17a. Calculate water quality and time functions based on the selected pattern.
[0095]
The water quality prediction unit 18 transmits the calculated water quality and time function to the water discharge calculation unit 19 via the signal line 18a, and the water quality calculation unit 19 performs the function based on the water quality and time function from the water quality prediction unit 18. Calculate water quality value corresponding to time. The water quality value corresponding to the time calculated by the water quality calculation unit 19 is transmitted to the determination unit 20 via the signal line 19a, and the determination unit 20 transmits the water quality corresponding to the time transmitted from the water quality calculation unit 19. And a deviation of the water quality value corresponding to the time from the preceding water quality meter 5 are calculated, and it is determined whether the calculated deviation is within a preset range. When the determination unit 20 determines that the calculated deviation is within a preset range, the determination unit 20 determines that the pre-stage water quality meter 5 is normal, and determines the water quality value from the pre-stage water quality meter 5 as the signal line 20a. To the load amount calculation unit 6. If the determination unit 20 determines that the calculated deviation is outside the preset range, the pre-stage water quality meter 5 determines that it is abnormal (failure, unsteady state due to calibration), and the water quality calculation unit 19 The water quality value is transmitted to the load amount calculation unit 6 through the signal line 20a. Here, the preset range is preset in the determination unit 20, but the determination unit 20 can freely change the setting.
[0096]
As described above, according to the present embodiment, even when an abnormality occurs in the pre-stage water quality meter 5, the load amount calculation unit 6 can calculate the pollutant load amount.
[0097]
Fourth embodiment
Next, a fourth embodiment of the present invention will be described with reference to FIG.
[0098]
FIG. 8 shows a fourth embodiment of the present invention.
[0099]
In the fourth embodiment shown in FIG. 8, a downstream water quality meter 22 for measuring the concentration of a specific substance in the water to be treated 3 is provided in the water distribution pipe c between the aerobic tank 12 and the final sedimentation tank 13, and the pollution load A target function setting unit 23 that sets a function between the amount and the target water quality of the treated water 3 is provided, and the function set in the target function setting unit 23 and the value of the pollution load from the load amount calculation unit 6 are set. A control target calculation unit 21 that calculates a control target value based on the control target value is provided.
[0100]
In FIG. 8, other configurations are substantially the same as those of the first embodiment shown in FIG. In FIG. 8, the same parts as those of the first embodiment shown in FIG.
[0101]
An ammonia concentration meter is used as the latter-stage water quality meter 22 shown in FIG.
[0102]
The control target calculation unit 21 is disposed between the load amount calculation unit 6 and the control unit 8, and a target function setting unit 23 is connected to the control target calculation unit 21.
[0103]
As shown in FIG. 8, the load amount calculation unit 6 calculates the pollution load amount, and transmits the calculated pollution load amount to the control target calculation unit 21 via the signal line 6 a.
[0104]
Next, the target function setting unit 23 sets a function (4.1) between the pollutant load and the ammonia concentration target value of the treated water 3 (FIG. 9). In FIG. 9, the vertical axis represents the ammonia concentration target value, and the horizontal axis represents the pollution load.
[0105]
Thereafter, the target function setting unit 23 calculates a function (a) of the pollutant load amount of the treated water 3 and the achievable ammonia concentration by simulation using the theoretical model of the IAWQ activated sludge model. Here, the target function setting unit 23 uses a theoretical model of the IAWQ activated sludge model, but other theoretical models may be used.
[0106]
Next, the target function setting unit 23 calculates a function (b) that gradually increases the ammonia concentration target value based on the function (a) calculated by the simulation, and this function (b) is used as the target function. It is set in the setting unit 23 (FIG. 10). In FIG. 10, the vertical axis represents the ammonia concentration target value, and the horizontal axis represents the pollution load.
[0107]
SV_NH4= H (P_NH4in) Formula (4.1)
In addition, each symbol in Formula (4.1) is set as follows.
H (P_NH4in): Pollution load / target function
SV_NH4: Ammonia concentration target value
[0108]
The function (b) set in the target function setting unit 23 is transmitted to the control target calculation unit 21 through the signal line 23a.
[0109]
The control target calculation unit 21 calculates an ammonia concentration target value (control target value) based on the function (4.1) set by the target function setting unit 23 and the value of the pollutant load amount from the load amount calculation unit 6. . The ammonia concentration target value calculated by the control target calculation unit 21 is transmitted to the control unit 8 via the signal line 21a.
[0110]
The control unit 8 determines the deviation e between the ammonia concentration target value calculated by the control target calculation unit 21 and the ammonia concentration value from the ammonia concentration meter 22._tIs calculated by the arithmetic expression (4.2), and based on the calculated deviation, the aeration amount target value Qair of the aeration apparatus 9 is calculated by the arithmetic expression (4.3)._tIs calculated.
[0111]
e_t= PV_{NH4, t}-SV_{NH4, t}          Formula (4.2)
Each symbol in equation (4.2) is set as follows.
[0112]
PV_{NH4, t}: Ammonia concentration of treated water 3 at time t (value transmitted from ammonia concentration meter 22)
SV_{NH4, t}: Ammonia concentration target value of the treated water 3 at time t (value calculated in the control target calculation unit 21)
Qair_t= Qair_t-Δt+ K_pe_t        Formula (4.3)
Each symbol in equation (4.3) is set as follows.
Qair_t: Aeration target value at time t
Qair_t-Δt: Aeration amount at time t-Δt
K_p: Proportional constant
Δt: time delay
[0113]
Proportional constant K_pThe time delay Δt is set in the control unit 8 in advance, but the control unit 8 can freely change the setting.
[0114]
The aeration amount target value calculated in the control unit 8 is transmitted to the aeration apparatus 9 via the signal line 8a, and the aeration apparatus 9 aerates the inside of the aerobic tank 12 with the aeration amount target value.
[0115]
As described above, according to the present embodiment,
In the target function setting unit 23, the function of the pollutant load amount of the treated water 3 and the achievable ammonia concentration (FIG. 9 (a)) is calculated by the simulation using the theoretical model of the IAWQ activated sludge model. On the basis of the function (FIG. 9 (a)), a function (FIG. 9 (b)) that gradually increases the ammonia concentration target value is calculated, and using this function (FIG. 9 (b)), When the pollution load amount of the water 3 becomes large, the aeration amount target value for the water to be treated 3 is gradually changed. Therefore, the aeration more than necessary can be suppressed, and the cost can be reduced.
[0116]
Next, a modified example of the present invention will be described.
[0117]
The control target calculation unit 21 calculates an ammonia concentration target value (control target value) based on the function (4.1) set by the target function setting unit 23 and the value of the pollutant load amount from the load amount calculation unit 6. However, according to the following equation (4.4) in consideration of the time point when the pollutant load amount of the treated water 3 is calculated and the time delay Δt until the treated water 3 flows into the aerobic tank 12: Ammonia concentration target value (control target value) SV_tMay be calculated.
[0118]
SV_t= H (P_t-Δt) Formula (4.4)
Each symbol in equation (4.4) is set as follows.
SV_t: Ammonia concentration target value
P_t-Δt: Pollution load in time (t 1 Δt)
Δt: time delay
[0119]
【The invention's effect】
According to the present invention, the amount of aeration by the aeration device can always be adjusted to an optimal amount, and the amount of flocculant injected can be adjusted to an optimal amount. Furthermore, when the amount of pollution load fluctuates greatly, the aeration apparatus can be controlled without aeration more than necessary, so that the cost can be reduced. In addition, since the control unit controls the flocculant injection device without using a water quality meter, it can solve the problem of deposits on the water quality meter and improve the reliability of the water quality control device for the sewage treatment plant. it can.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing a first embodiment of a sewage treatment plant water quality control apparatus according to the present invention.
FIG. 2 is a graph showing the relationship between UV value and phosphorus concentration of water to be treated.
FIG. 3 is an overall configuration diagram showing a second embodiment of a sewage treatment plant water quality control apparatus according to the present invention.
FIG. 4 is a diagram showing a water quality database.
FIG. 5 shows the relationship between water quality and time
FIG. 6 is a diagram showing a relationship between a threshold value of a pollutant load amount and a pollutant load amount
FIG. 7 is an overall configuration diagram showing a third embodiment of a sewage treatment plant water quality control device according to the present invention;
FIG. 8 is an overall configuration diagram showing a fourth embodiment of a sewage treatment plant water quality control apparatus according to the present invention.
FIG. 9 is a diagram showing a function of the pollutant load of treated water and the achievable ammonia concentration
FIG. 10 is a diagram illustrating a target function set in a target function setting unit.
FIG. 11 is a diagram showing a conventional advanced processing process.
FIG. 12 shows a conventional sewage treatment plant water quality control device.
[Explanation of symbols]
1 Sewage treatment plant water quality control equipment
4 Flow meter
5 Pre-stage water quality meter
6 Load calculation unit
7 Standard setting section
8 Control unit
9 Aeration equipment
12 Aerobic tank
16 Coagulant injection device
17 Water quality database
18 Water quality prediction department
19 Water quality calculator
20 judgment part
21 Control target calculation section
22 Rear water quality meter
23 Target function setting section

Claims (1)

In the sewage treatment plant water quality control device installed in the sewage treatment plant that treats the incoming treated water,
Aerobic tank,
A flow meter that is provided in the front stage of the aerobic tank and measures the flow rate of water to be treated
A pre-stage water quality meter that is provided in the front stage of the aerobic tank and measures the concentration of nitrogen components in the treated water;
A latter-stage water quality meter that is provided in the latter stage of the aerobic tank and measures the concentration of ammonia in the treated water;
A load amount calculation unit for calculating a pollutant load based on information from the flow meter and the previous water quality meter,
A reference setting unit for setting a reference value of the pollution load,
A function between the pollutant load and the target concentration of ammonia to be treated is set. At this time, when the pollutant load increases, the target concentration of ammonia to be treated increases gradually in steps, and the same. A target function setting unit that sets a function so that the target concentration approaches the concentration that can be achieved in the treatment of ammonia in the amount of pollution load of
A control target calculation unit for calculating a control target value based on the function set in the target function setting unit and the value of the pollutant load from the load calculation unit;
An aeration device for aeration in an aerobic tank;
A sewage treatment plant water quality control comprising: a control unit that controls an aeration apparatus based on a deviation between a control target value calculated by a control target calculation unit and a value of ammonia concentration from a subsequent water quality meter apparatus.

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